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Essentials of Management Information Systems Chapter 7 Chapter 7 Managing Data Resources Managing Data Resources 7.1 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Case Study • United Asset Coverage (UAC) is a provider of maintenance services for office equipment • Problem: data used by sales, marketing, customer service, and accounting department were scattered in several isolated information systems • Solution: E-business suite to organize data based on an enterprise-wide relational database 7.2 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Objectives 1. Why do businesses have trouble finding the information they need in their information systems? 2. How does a database management system help businesses improve the organization of their information? 7.3 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Objectives 3. How do the principal types of database models affect the way businesses can access and use information? 4. What are the managerial and organizational requirements of a database environment? 5. What new tools and technologies can make databases more accessible and useful? 7.4 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Management Challenges 1. Organizational obstacles to a database environment 2. Cost/benefit considerations 7.5 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Organizing Data in a Traditional File Environment File Organization Terms and Concepts • Bit: Smallest unit of data; binary digit (0,1) • Byte: Group of bits that represents a single character • Field: Group of words or complete number • Record: Group of related fields • File: Group of records of the same type 7.6 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Organizing Data in a Traditional File Environment File Organization Terms and Concepts • Database: Group of related files • Entity: Person, place, thing, or event about which information must be kept • Attribute: A piece of information describing a particular entity • Key field: Field that uniquely identifies every record in a file 7.7 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Organizing Data in a Traditional File Environment The data hierarchy Figure 7-1 7.8 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Organizing Data in a Traditional File Environment Entities and attributes Figure 7-2 7.9 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Organizing Data in a Traditional File Environment Problems with the Traditional File Environment • Data redundancy • Program-data dependence • Lack of flexibility • Poor security • Lack of data-sharing and availability 7.10 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Organizing Data in a Traditional File Environment Traditional file processing Figure 7-3 7.11 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Database Management Systems Database • Collection of centralized data • Controls redundant data • Data stored so as to appear to users in one location • Services multiple application 7.12 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management The contemporary database environment Figure 7-4 7.13 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Database Management Systems Database Management System (DBMS) • Creates and maintains databases • Eliminates requirement for data definition statements • Acts as interface between application programs and physical data files • Separates logical and physical views of data 7.14 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Database Management Systems Three Components to a DBMS 1. Data definition language: Formal language programmers use to specify structure of database 2. Data manipulation language: For extracting data from database, e.g. SQL 3. Data dictionary: Tool for storing, organizing definitions of data elements and data characteristics 7.15 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Sample data dictionary report Figure 7-5 7.16 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Database Management Systems How a DBMS Solves Problems of a Traditional File Environment • • • • • 7.17 Reduces data redundancy Eliminates data inconsistency Uncouples programs from data Increases access and availability of data Allows central management of data, data use, and security © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Types of Databases Relational DBMS • Represents data as two-dimensional tables called relations • Relates data across tables based on common data element • Examples: DB2, Oracle, MS SQL Server 7.18 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management The relational data model Figure 7-6 7.19 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Types of Databases Three Basic Operations in a Relational Database • Select: Creates subset of rows that meet specific criteria • Join: Combines relational tables to provide users with information • Project: Enables users to create new tables containing only relevant information 7.20 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management The three basic operations of a relational DBMS Figure 7-7 7.21 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Types of Databases Hierarchical DBMS • Older system presenting data in tree-like structure • Models one-to-many parent-child relationships • Found in large legacy systems requiring intensive highvolume transactions: Banks; insurance companies • Examples: IBMs IMS 7.22 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management A hierarchical database for a human resources system Figure 7-8 7.23 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Types of Databases Network DBMS • Older logical database model • Models many-to-many parent-child relationships • Example: Student – course relationship: Each student has many courses; each course has many students 7.24 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management The network data model Figure 7-9 7.25 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Types of Databases Disadvantages of Hierarchical and Network DBMS • Outdated • Less flexible compared to RDBMS • Lack support for ad-hoc and English language-like queries 7.26 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources The Database Approach to Data Management Types of Databases Object-Oriented Databases (OODBMS) • Stores data and procedures as objects • Better able to handle graphics and recursive data • Data models more flexible • Slower than RDBMS • Hybrid: object-relational DBMS 7.27 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment Designing Databases Two Design Exercises in Creating Database • Conceptual (logical) design: Abstract model of database from business perspective • Physical design: How the database is actually arranged on direct access storage devices 7.28 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment Designing Databases Conceptual Database Design • Identifies relationships between data elements • Identifies most efficient way to group data elements • Identifies redundant data elements • Identifies grouping of data elements needed for specific applications 7.29 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment Designing Databases Entity-Relationship Diagram A methodology for documenting databases that illustrates the relationship between various elements in the database Normalization The process of creating small, stable, and adaptive relations (tables) from complex groups of data when designing a relational database 7.30 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment An entity-relationship diagram Figure 7-10 7.31 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment An unnormalized relation for ORDER Figure 7-11 7.32 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment A normalized relation for ORDER Figure 7-12 7.33 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment Distributing Databases Distributed Database • • • • • • 7.34 Partitioned or replicated to more than one location Increases service and responsiveness Reduces vulnerability of single, massive central site Depend on telecommunication lines Pose security risks through distribution of sensitive data Central data must be updated or justified with local data © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment Distributed databases Figure 7-13 7.35 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment Key organizational elements in the database environment Figure 7-14 7.36 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment Management Requirements for Database Systems Data Administration • • • • Develop information policy Define information requirements Plan for data Oversee logical database design and database dictionary development • Monitor use of information 7.37 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Creating a Database Environment Management Requirements for Database Systems Data Planning and Modeling Methodology • Enterprise-wide planning for data • Identify key entities, attributes, and relationships that constitute the organization’s data 7.38 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Multidimensional Data Analysis Online Analytical Processing (OLAP) • Multidimensional data analysis • Enables users to view the same data in different ways using multiple dimensions • Each aspect of information – product, price, region – represents a different dimension 7.39 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Multidimensional data model Figure 7-15 7.40 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Data Warehouses and Datamining • Data warehouse: Stores current and historical data for reporting, analysis • Data mart: Subset of data warehouse with summary of data for specific users • Datamining: Techniques to find hidden patterns, relationships in large pools of data to infer rules for predicting future trends 7.41 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Components of a data warehouse Figure 7-16 7.42 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Data Warehouses and Datamining Benefits of Data Warehouses • Improved information and accessibility • Ability to model and remodel data • Enable access to data without affecting performance of underlying operational legacy systems 7.43 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Window on Management Data Reveal New Sales Opportunities • How did the use of data warehouses and datamining help management at these companies make better decisions? • What value do these systems provide? 7.44 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Data Warehouses and Datamining Hypermedia database • Organizes data as network of nodes • Links nodes in pattern specified by user • Supports text, graphic, sound, video and executable programs 7.45 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends A hypermedia database Figure 7-17 7.46 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Databases and the Web Linking Internal Databases to the Web • Database server: – Hosts DBMS – Receives SQL requests – Provides required data • Middleware: – Works between Web server and DBMS to take requests – Handles connectivity to database – Can be application server in PHP or CGI scripts 7.47 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Linking internal databases to the Web Figure 7-18 7.48 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Database Trends Databases and the Web Advantages to Web Access to Databases • Browser software easy to use; little training • Web interface requires no changes to internal database • Costs less than custom interfaces 7.49 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Databases in the Cloud Contemporary Hardware Trends • Cloud Computing: • A model of computing in which firms and individuals obtain computing resources over the Internet • Cloud infrastructure as a service • Cloud platform as a service • Cloud software as a service • Public vs. private clouds • Utility computing, on-demand computing • Data storage security is in hands of provider 7.50 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Databases in the Cloud Cloud Computing Platform In cloud computing, hardware and software capabilities are provided as services over the Internet. Businesses and employees have access to applications and IT infrastructure anywhere at any time using an Internetconnected device. 7.51 © Prentice Hall Essentials of Management Information Systems Chapter 7 Managing Data Resources Databases in the Cloud • Cloud computing providers offer database management services, but typically with less functionality • By moving to a cloud solution, companies are able to scale their computing resources in response to real-time demand while keeping costs low 7.52 © Prentice Hall